Solar power generation is a typical green power generation with many advantages including its safety, reliability, free of noises, free of pollutions, free of regional limitations, generating power without consuming fuels, requiring no mechanical parts, low failure rate, requiring no patrol or staff on duty, and conveniently combined with a building. These advantages are incomparable among regular power generations and other power generations. The application of solar power is an ideal solution for solving the issue of a continuous development of power by human beings. Countries including Japan, U.S.A., Germany, Netherlands, Italy, Spain, Switzerland, Finland, Austria, England and Canada have established their own development plans for solar power generation. In the new century, these plans are passed in hope of having a strong competitiveness on the research and application of the new green energy.
In the studies of comparing sun-tracking power generation systems and general fixed solar power generation systems, the sun-tracking system has a larger number of hours of sunlight projection daily than the fixed solar power generation systems and is used mainly by satellites or experimental mechanical structures for effectively enhancing system performance and reducing the number of equipments used in the system.
At present, the sun-tracking power generation systems generally use a support stand for supporting a solar panel and adopt a direct rotating design. If a lens for collecting light is installed, then the lens is rotated together with a solar cell. Some systems use a large mirror for reflecting and gathering sunlight or adopt a design of a solar tracking system with springs or a solar tracking system with airbags. Some researches in foreign countries adopt a design of using a shape memory alloy to turn a solar cell towards the sun. In general, the volume of most solar tracking systems having a motor is huge, and the motor consumes lots of power during the tracking process performed by the motor. Furthermore, a huge space is required, and thus it is not easy to move or install such systems. For designs without using a motor, the tracking speed is too slow and unable to timely track the position of the sun due to the limitations of the mechanical structure or its components.
With reference to U.S. Pat. No. 6,123,067 entitled “Solar collector tracking system”, a solar energy collector of the tracking system has a multiple of lens modules installed on a front surface which is a central protection mechanical structure disposed at a horizontal shaft of an azimuth platform equipment for protecting a solar energy collector installed on a back surface. An important hydraulic height driving device is installed at the horizontal shaft of the azimuth platform equipment and a piston rod at the front end and connected to the solar energy collector at the rear surface, such that the tracking system is situated at a vertical operating position with a light projection angle substantially equal to 90° and a transversal storing position. A journal of the azimuth platform equipment is extended from the ground to the top of a tower, and a tubular support pillar is provided for protecting the top of the journal. A driving head is extended horizontally on the tubular support pillar and includes a pivot pin extended upward. The front end of the piston rod for primary and second azimuth angle hydraulic driving devices is coupled to the pivot pin. Both ends of the reverse side of the azimuth angle hydraulic driving device protect the interior of the azimuth platform equipment. A hydraulic power device is connected to its hydraulic driving device. An electronic controller receives a signal transmitted from an azimuth encoder transducer and an elevation encoder transducer to move both internal and external piston rods of each hydraulic driving device and rotate the solar energy collector for tracking the sun.
With reference to U.S. Pat. No. 6,363,928 entitled “Solar collection system”, the solar tracking mechanical structure is a part of the solar energy collection system. The collection system comprises a light-reflecting housing for gathering the radiation of sunlight to a tube for absorbing the radiation. A thermal conductive fluid is contained in the tube. The reflecting housing is mounted onto a support stand. A driving device is installed between the support stand and the reflecting housing. A solar energy sensor is installed deeply into a visible tube, and the visible tube fixed onto the reflecting housing. At least one line in the visible tube is parallel to the optical axis of the reflecting housing. The solar energy sensor generates a sensing signal serving as a control input of the driving control system. When a limit switch generates a limit stop signal, the reflecting housing reaches its maximum angular position. The driving control system produces a fluid flow based on the solar energy sensor signal and the limit stop signal. This method tracks the sun and also provides a solar cell array.
Since the applications of solar cell emphasize on the enhancement of electric generation efficiency and the reduction of power consumption, therefore it is a subject for the related industry to overcome the aforementioned issues by developing an effective solar tracking system to reduce the system weight and the power consumption while improving the electric power generating efficiency of the solar cell.